We propose a conference designed to further our understanding of how infants and children acquire and learn to use spatial language -- the language we use to talk about objects, events, and spatial relationships in the world. Spatial language and spatial cognition are fundamental to human knowledge, and therefore serve as a key domain within which to ask about how language develops from pre-linguistic foundations, and how it later comes to affect spatial thinking. Specific topics will include (a) how spatial cognition in infancy supports the acquisition of spatial language, (b) how cross-linguistic distinctions in spatial language are acquired, and (c) how, once acquired, spatial language affects spatial thought. We plan to invite scholars with interdisciplinary perspectives on these problems, including linguists, psychologists, and computer scientists who work on problems of the representation of spatial language and learning. The conference will take place at Johns Hopkins University on June 6-8, 2003, and will include a set of target talks and commentaries, which should stimulate interdisciplinary discussion. The product of the conference will be a published volume or volumes which provide interdisciplinary perspectives on questions of how spatial language is acquired, how it engages spatial cognition in infancy, and how it later affects spatial thought.